Lightest pseudoscalar exchange contribution to light-by-light scattering piece of the muon g-2

TL;DR

This paper calculates the contribution of the lightest pseudoscalar mesons to the light-by-light scattering part of the muon g-2 using a resonance chiral Lagrangian, achieving results consistent with previous estimates but with reduced uncertainty.

Contribution

It provides a refined calculation of pseudoscalar exchange contributions to muon g-2 using a resonance chiral Lagrangian with minimal violations of short-distance constraints.

Findings

Calculated pseudoscalar contribution to muon g-2 as (10.47±0.54)×10^-10

Achieved good agreement with experimental TFF data and previous estimates

Reduced the uncertainty in the pseudoscalar exchange contribution

Abstract

Lightest pseudoscalar (P= pi^0, eta, eta') exchange contribution to the light-by-light (LbL) scattering piece of the muon anomaly, a_mu=(g_mu-2)/2, has been evaluated using a resonance chiral Lagrangian (R\chi L). Best description of pion transition form-factor (TFF) data is obtained with only tiny violations of one of the relations in the minimal consistent set of short-distance constraints on the anomalous R\chi L couplings. eta^{(')} TFF, predicted in terms of the pi TFF and the eta-eta^' mixing, are in good agreement with measurements. With this input, we obtain a_mu^{P,LbL} = (10.47\pm0.54)x10^-10, consistent with the reference determinations in the literature, albeit with smaller error.